When Europe’s defence ministers gathered in Brussels this week, all eyes were on the newcomer: Sylvie Goulard, the former liberal MEP who had been appointed France’s armed forces minister less than 24 hours earlier.

But the meeting – to discuss ways of boosting EU-Nato cooperation and the use of joint EU battle groups – was remarkable for more than that. All five of the bloc’s largest economies, apart from Britain, were represented by women.

“I’d like to think the glass ceiling has been broken,” said Alexandra Ashbourne-Walmsley, an associate fellow of the Royal United Services Institute. “It shouldn’t be a thing any more. But actually it will be until the US has a female defence secretary.”

Indira Gandhi became the first high-profile female defence minister in 1975. The first in Europe was Finland’s Elisabeth Rehn in 1990. Since then 18 European countries have followed suit, including Sweden three times and Norway five.

Few have direct military experience: of the current crop, Von der Leyen is a medical doctor by training, Goulard and Hennis-Plasschaert have spent years in Brussels, Cospedal is a career diplomat and Pinotti has a literature and politics degree.

But in a field traditionally dominated by men, the growing prevalence of women could reflect both their capacity for “multitasking and thinking on their feet” and the changing nature of the portfolio, Ashbourne-Walmsley said.

“Defence is a complex and fast-moving job,” she said. “Unexpected things happen. It will include, for example, cyber-warfare and other less conventional forms of warfare. It’s also often about finding consensus, building alliances.”

Nor can it realistically be seen as less of a top-tier job than other cabinet posts, like foreign or economic affairs. “That may have been the case even five years ago, but it certainly isn’t any longer,” Ashbourne-Walmsley said.

“If you look at the multiplication of potential threats many countries face – the thinking now about Russia, the terror threat – and general world instability right now … Defence is really no longer down the agenda.”

But Ashbourne-Walmsley said that in the case of France in particular, defence was “really a very senior job indeed. With the UK leaving the EU, France will be Europe’s defence heavyweight. It’s a nuclear power, it has a very significant military.”

Goulard will be a key figure in European defence at a time when the continent is moving steadily towards closer cooperation in the light of the uncertainty triggered by the election of Donald Trump and doubts about US commitment to Nato.

Her fellow EU defence ministers are also significant domestic players. Von der Leyen, a mother of seven, is often mentioned as a potential successor to the German chancellor, Angela Merkel.

Hennis-Plasschaert, who said on taking office in 2012 that “it doesn’t matter if you have a willy or not”, has frequently denied women have a common way of doing politics just because they are women.

They found that equality between men and women in a country was a good predictor of when it would appoint a female defence chief – but that military dictatorships and countries with big defence budgets tended not to.

“Large military expenditures suggest a political climate that is not conducive to changing norms of female exclusion,” the academics concluded.